return {
  postgres = {
    up = [[
    ]],
  },
  cassandra = {
    up = [[
    ]],
  },
  mysql = {
    up = [[
      CREATE TABLE `cluster_pods`(
        `id`                varchar(50) PRIMARY KEY,
        `pod_hostname`      varchar(50),
        `pod_start_time`    timestamp,
        `pod_last_seen`     timestamp,
        `pod_last_reload`   timestamp,
        `pod_version_id`    varchar(50),
        `pod_version_time`  timestamp,
        `pod_ip`            varchar(50),
        `pod_plugins`       text,
        `cluster_id`        varchar(50),
        `bool`              bool,
        UNIQUE INDEX `cluster_pods_pod_hostname_key` (`pod_hostname`),
        INDEX `cluster_pods_ip_idx`(`pod_ip`),
        INDEX `cluster_pods_cluster_id_idx`(`cluster_id`),
        INDEX `cluster_pods_pod_hostname_idx`(`pod_hostname`)
      )ENGINE=INNODB DEFAULT CHARSET=utf8;

      CREATE TABLE `clusters` (
        `id` varchar(50) PRIMARY KEY ,
        `cluster_name` varchar(50),
        `master_pod_name` varchar(50),
        `master_pod_last_seen` timestamp,
        `master_pod_ip` varchar(50),
        UNIQUE INDEX `cluster_cluster_name_key` (`cluster_name`),
        INDEX `cluster_master_pod_name_idx` (`master_pod_name`)
      ) ENGINE=InnoDB DEFAULT CHARSET=utf8;

      INSERT INTO `schema_meta`
        (`key`,
        subsystem,
        last_executed,
        executed,
        pending)
      VALUES
        ('schema_meta',
        'cluster_pods',
        '000_base_cluster_pods',
        '{000_base_cluster_pods}',
        NULL);

      DROP EVENT IF EXISTS delete_expired_cluster_pods_info;
      CREATE EVENT delete_expired_cluster_pods_info
      ON SCHEDULE EVERY 3 MINUTE
      ON COMPLETION PRESERVE
      DO
      BEGIN
        DELETE
        FROM cluster_pods
        WHERE pod_last_seen <= DATE_SUB(CURRENT_TIMESTAMP(), INTERVAL 3 MINUTE) ;
      END;
    ]],
  },
}
